Yegorova-Gudkova T, Bojko M, Neustroiev Y, Khostash O, Pan L, Shepitko H, Beloborodko V, Zvirkov O, Kirilina M, Matjukhina I. Development of an innovative methodology of research of systems on an example of a shadow economy as an invariant of system of economic security of state. TAPR [Internet]. 2021Jul.31 [cited 2024Jul.18];4(4(60):41-5. Available from: https://journals.uran.ua/tarp/article/view/239035